By Stefan Amisten – Medical Writer, Expert & Research Scientist
What is diabetes?
Diabetes is a chronic disease that occurs when the pancreas is no longer able to make the hormone insulin, or when the body cannot respond appropriately to the insulin that it produces. The body uses glucose from the foods we eat for energy, or to store it for future use. This means that if diabetes is left untreated, it can lead to elevated levels of blood glucose.
Insulin resistance, which is common in type 2 diabetes, is when the body no longer responds adequately to the insulin that is being produced. Insulin resistance is closely associated with obesity. The risk of type 2 diabetes is mainly determined by environmental and lifestyle factors, which means that understanding what these lifestyle factors are is a first step towards reducing the risk or delaying the onset of type 2 diabetes.
What causes diabetes?
Weight gain in middle‐aged adults can often be a result of excess caloric intake from refined sugars and highly processed carbohydrates such as potatoes and crisps, pasta and sugar‐sweetened beverages. Whereas consumption of fruit, vegetables, nuts, whole grains, and low-fat dairy may help prevent weight gain. Overall, a so‐called ‘Western diet’, contains large amounts of high glycaemic index carbohydrate rich–foods, which is associated with an increased risk of developing insulin resistance, obesity, type 2 diabetes, hypertension and cancer.
Lack of physical activity
A lack of physical activity in adolescence predisposes for obesity in young adulthood. In fact, around 1 million deaths per year in Europe are attributable to physical inactivity, which is the underlying cause of 7% of all European type 2 diabetes cases.
Most individuals with type 2 diabetes are either overweight (BMI 25‐30 kg/m2) or obese (BMI 30 kg/m2 or above), which increases the risk for developing type 2 diabetes. Obesity is influenced not only by diet but also physical inactivity. Additionally, obesity has been associated with an increased risk of cancer, hypertension, stroke and cardiovascular disease in both men and women.
Lifestyle factors that decrease the risk of developing type 2 diabetes
A healthy diet that helps reduce the risk of type 2 diabetes is rich in vegetables, fruits, nuts, legumes and whole grains, and low in red or processed meats, sugar‐sweetened beverages and refined grains.
Physical activity is a key intervention for the management of type 2 diabetes, as regular physical exercise improves blood glucose control and may also delay or reduce the risk of type 2 diabetes, hypertension and cardiovascular disease. In fact, structured interventions combining physical activity with modest weight loss more than halves the risk of type 2 diabetes in high‐risk populations.The NHS therefore recommends incorporation of at least 2.5 hours per week of moderate to vigorous physical activity as part of lifestyle changes to prevent type 2 diabetes onset in high‐risk adults.
Overweight adults with elevated blood glucose levels may delay the onset or decrease the risk of developing type 2 diabetes by losing weight, and these protective effects appear to be sustained for more than 10 years. In overweight and obese individuals with type 2 diabetes, even modest weight loss (~5% of total body weight) improves glycaemic control. To put this in perspective, a 5% total body weight reduction equals 3.75, 5 or 6.25 kg for people weighing 75, 100 or 125 kg, respectively. Based on these findings, Diabetes UK recommends that people at risk of diabetes should aim for a 5% body weight reduction, and also increase their moderate physical activity to at least 2.5 hours per week to prevent or delay the onset of type 2 diabetes.
Type 2 diabetes is a worldwide epidemic that is influenced by several lifestyle factors such as diet, lack of exercise and obesity. Modest lifestyle changes such as eating more vegetables, fruits, nuts, legumes and whole grains and less red meat, modest exercise such as walking at least 2.5 hours every week, and 5–7% body weight loss may reduce the risk of type 2 diabetes in high‐risk individuals.